nir2dxil: Lower texture projections
Since DXIL doesn't have texture projection instructions, all of them must be lowered, as it's stated down the road (this PR avoids that case from being hit): https://gitlab.freedesktop.org/mesa/mesa/-/blob/2e774180c61b7928329fb38652d2a54d0495c9e2/src/microsoft/compiler/nir_to_dxil.c#L5076